عنوان مقاله [English]
Motor and field characteristic change is called variability of practice that the learner experiences during skill practice. This study was designed to compare the effect of variability of practice on the basketball free-throw learning in implicit and explicit conditions. For this purpose, 40 male (20-27 years old) Shahid Beheshti University students were voluntarily selected and were randomly divided into four groups: implicit learning with variable practice, implicit learning with constant practice, explicit learning with variable practice and explicit learning with constant practice after a pretest. Variable practice groups performed 45 throws from 1.5, 3 and 4 meters distances from the target while constant practice groups had these throws from 3 meters distance each session for 6 days. Implicit learning groups performed a secondary task of counting from 1000 in a reverse order for every triad number along with the free-throw task. But the explicit learning groups performed the free-throw task without a secondary task. The acquisition, retention (48 hours after the last acquisition phase) and transfer (from a 4.6 meters distance) tests were conducted. For data analysis, analysis of variance with repeated measures, two-way ANOVA and Tukey post hoc test were used (P<0.05). The results showed that all groups improved in the acquisition phase (P>0.001) while the main effect of learning and practice was not significant (P>0.05). In addition, in the retention and transfer phases, the main effect of learning type, practice type and the interaction between practice and learning was not significant (P>0.05). Therefore, the results of the present study disagreed with Schmidt's schema theory.
6. Brady, F. (1998). A theoretical and empirical review of the contextual interference effect and the learning of motor skills. Quest50(3):266-93.
7. Brady, F. (2008). The contextual intrference effect and sport skils. Perceptual and motor skills. 106(2):461-72.
8. Goodwin, JE., Grimes, CR., Eckerson, JM. and Gordon, PM. (1998). Effect of different quantities of variable practice on acquisition, retention, and transfer of an applied motor skill. Perceptual and motor skills. 87(1):147-51.
9. Goodwin, JE. nad Jones, HA. (2003).Effect of Specific and Variable Practice on Learning an Archery Target Shot. Research quarterly for exercise and sport. 74 (1). 126-37.
10. Green, TD. and Flowers JH.(1991). Implicit versus explicit learning processes in a probabilistic, continuous fine-motorcatching task. Journal of Motor Behavior. 23(4):293-300.
11. Heitman, RJ., Pugh, SF., Kovaleski, JE., Norell, PM. and Vicory, JR. (2005). Effects of specific versus variable practice on the retention and transfer of a continuous motor skill. Perceptual and motor skills.100 (3c): 1107-13.
12. Keith, D. and Myers, C. (1990). The role of tacit knowledge in human skill performance. Journal of Human Movement Studies. 19(6):273-88.
13. Kerr, R. and Booth, B. (1978). Specific and varied practice of motor skill. Perceptual and Motor Skills; Perceptual and Motor Skills.Vol 46(2): 395-401.
14. Lam W, Maxwell J, Masters R. (2009). Analogy versus explicit learning of a modified basketball shooting task: Performance and kinematic outcomes. Journal of sports sciences. 27(2):179-91.
15. Liao CM, Masters RSW.(2001).Analogy learning: A means to implicit motor learning. Journal of sports sciences.19(5):307-19.
16. Lee, Timothy, D. and Simon, DA. (2004). Contextual interference. Skill Acquisition in sport: Research, theory, and practice: 29–44
17. Masters RSW, Maxwell JP. (2004). 10 Implicit motor learning, reinvestment and movement disruption. Skill acquisition in sport: Research, theory and practice:207-228.
18. Megan, A. Rendell. Damian, Farrow. and Tony, Morris. (2011). An Implicit Basis for the Retention Benefits of Random Practice. Journal of Motor Behavior, 43(1).1-13.
19. McCracken, HD. nad Stelmach, GE. (1977). A test of the schema theory of discrete motor learning. Journal of Motor Behavior.9(3).193-201.
20. Poolton, JM., Masters, RSW. and Maxwell, JP. (2005). The relationship between initial errorless learning conditions and subsequent performance. Human Movement Science, 24,362-378.
21. Poolton, J., Maxwell, J., Masters, R. and Raab, M. (2006). Benefits of an external focus of attention: Common coding or conscious processing? Journal of sports sciences. 24(1):89-99.
22. Sekiya, AH. (2006). Contextual interference in implicit and explicit motor learning 1. Perceptual and motor skills.103(2):333-43.
23. Shea, CH. and Kohl, RM. (1990). Specificity and variability of practice. Research quarterly for exercise and sport.61(2):169.
24. Shea, C. and Kohl, R. (1991). Composition of practice: Influence on the retention of motor skills. Research quarterly for exercise and sport. 62(2):187-95.
25. Shea, CH., Wulf, G., Whitacre, CA. and Park, JH. (2001). Surfing the implicit wave. The Quarterly Journal of Experimental Psychology: Section A. 54(3):841-62.
26. Wulf, G. (1991). The effect of type of practice on motor learning in children. Applied Cognitive Psychology. 5(2):123-34.
27. Wulf G., Hob, M. and Prinz, W. (1998). Instructions for motor learning: Differential effects of internal versus external focus of attention. Journal of Motor Behavior. 30(2):169-79.
28. Wulf, G., Raupach, M. and Pfeiffer, F. (2005). Self-controlled observational practice enhances learning. Research quarterly for exercise and sport. 76(1):107-11.
29. Wulf, G. nad Schmidt, RA. (1997). Variability of practice and implicit motor learning. Journal of Experimental Psychology: Learning, Memory, and Cognition. 23(4):87-106.
30. Wulf, G. and Weigelt, C. (1997). Instructions about physical principles in learning a complex motor skill: to tell or not to tell.Research quarterly for exercise and sport. 68(4):362.
31. Yan JHT, J.R. , Thomas, K.T. The effect of practice variability. A quantitative review,”Washinsgon. Jun 1998;Vol. 69, Iss .(2): 210, 6.